Consider a Project Having the Following Seven Activities

Consider a project having the following seven activities:
Normal Normal Crash Crash Maximum
Immediate Time Cost Time Cost Weeks
Activity Predecessors (weeks) ($) (weeks) ($) Reduced
A none 4 3,000 3 5,000 1
B A 9 5,000 7 8,000 2
C A 4 7,000 4 7,000 0
D B, C 6 6,000 4 8,000 2
E C 8 4,000 6 8,000 2
F D 3 4,000 2 9,000 1
G E, F 4 2,000 2 7,000 2
(a)What is the expected project completion time?
(b)What is the critical path?
(c)What is the most economical way and how much will it cost to reduce the completion time of the project by three weeks? By five weeks?